Apparatus for making expansion couplings



April 30, 1929. P. J. SHRUM APPARATUS FOR MAKING EXPANSION COUPLINGS ,ZIO

IHIHW'M H llll ll B R 2:: l M. 5 2 3 8/ 9 1 z 2 2 n Mm .4 v I A .7 w 5 mm 2 E/V/ M/ b b \E 1 Z5 L 4 AWL April 30, 1929. P. J. SHRUM 1,711,132

I APPARATUS FOR MAKING EXI ANSION COUPLINGS Filed May 11, 1926 2 Sheets-Sheet 2 Z7 27 22 I 24w 5 23 6 2'5 2'4 25 .26 1 .15 12 7 6 I 12 J 15 I |5 r. I

Patented Apr. 30, 1929.

PATENT OFFICEQ PETER J. simi ar, or MoNAoA, rENNsYLvANIA, ASSIGNOB. To coiLoNA MANUFAC- TURI G COMPANY, 011 PITTSBURGH, PENNSYLVANIA, A CORPORATION or PENN;

SYLVANIA.

ArPARATUs Ron MAKING EXPANSION COUPLINGS.

Application filed May 11,

This invention relates to the manufacture of pipe couplings, and more particularly to the manufacture of couplings having a corrugation or rib therein which imparts flexibility to the coupling whereby a pipe line in which the couplings are used may be free to expand or contract without liability of injury thereto.

Pipe couplings of the type referred to consist merely in a cylindrical metal body which is expanded outwardly to form a rib or corrugation therein. This rib or corrugation is located intermediate the ends of the cylindrical body and preferably at the center thereof. It is completely annular, and its purpose is to permit the opposite ends of the couplings to move toward or away from each other to allow for the expansion and contraction of the pipe line of which the coupling is a part. The ends of couplings of, this character may be beveled to facilitate their being welded into a pipe line, or they may be threaded so that they can be screwed into adjoining pipe ends.

The present invention has for its object to provide an apparatus for the formation of couplings of this type from a cylindrical metal body, such as a short length of standard pipe. The invention has for a further object to provide an apparatus for the formation of a coupling between-pressing dies in such manner as to subject the metal to as little strain as possible whereby the production of faults in the metal by reason of the pressing operation is minimized. A further object of the invention is to provide means for the rapid and accurate production of such couplings.

The invention may be readily understood by reference to the accompanying drawings which illustrate a preferred embodiment of the invention but to the details of which the invention is not confined, as various changes and modifications may be made within the spirit and contemplation of the invention.

In the drawings Figure 1 represents a vertical section through the forming dies showing a blank to be formed positioned therein;

Figure 2 is a view similar to Figure 1 showing the dies at the completionof the pressing stroke with the formed blank ready to be ejected therefrom;

1926. Serial No. 108,298."

Figure 3 is a side-elevation on a small scale showing the completed coupling unit.

According to my invention, the coupling is formed between two dies, at least one of which is movable toward and away from the other. I have shown an arrangement where- 1n there is a fixed lower die designated A and an upper vertically movable die desig nated B.

The lower die member A includes'a base member or block'2 having a centralv pin or plug 3 thereon. The plug 3 is preferably removable from a base and is secured thereto by abolt 4. The upper face of the block 2 has a recessed portion 5 about which is an annular rim 6. Received in the recessed portion 5 of the base member 2 is a cylindrical block 7 having a central opening 8 therein to receive the center block 3. The opening 8 is enlarged below the top thereof to provide a shoulder therein. at 9. Interposed between this shoulder and the base of the plug 3 is a heavy compression spring 10 which tends to urge the block 7 upwardly. Figure 1 shows the block 7 raised to its normal position while Figure 2 shows the block depressed to the position it assumes at the completion of the pressing stroke. The block 7 preferably has a ledge around the bottom thereof on which is set and to which is secured a ring 12 which is part of the forming die structure.

Secured on the rim orfiange 6 is a fixed ring 13. The lower innermost edge of the ring 13 projects over a shoulder 14: on the extreme periphery of the member 7. The shoulder 14 will therefore contact with the lower innermost edge of the member 13, which edge is designated 13 to limit the upward movement of the member 7 and the p arts associated therewith. The upper inner edge of the member 13, which upper edge is designated 13 is outwardly rounded as clearly shown in the drawings. The extreme lower portionof the ring 12 is of such diameter that the ring fits snugly in the outer ring 13. The upper part of the ring 12 is of less diameter than. the ring 13 so as to provide an annular groove or recess 16 of considerable depth between the rings 12 and 13. On the member 12 is a shoulder 12 at the point where the diameter thereof is increased, and; this shoulder is preferably downwardly and i11 wardly inclined.

Passing through the rim 6 of the member 2 at suitable points of one or more, and preferably two vertically reciprocal rods 17 having shoulders 18 thereon which cooperate with springs 19 in a cavity in the base member 2. These springs urge the rods 17 to the retracted position shown in Figure 1, but the rods 17 may be lifted against the pressure of these springs by mechanism associated with the press and not shown in the present drawings. These rods are the usual ejector rods commonly provided on metal pressing machines of this character.

The upper die member B is generally similar but somewhat more simple than the lower die member A. The upper die member I; includes a carrier block 20 having a recessed lower face 21 and a rim or flange portion 22 around the outer edge thereof. Fixed to the rim or flange 22 is a ring 23 whose inside diameter is the same as the inside diameter of the lower ring 13. The inner lower edge 23 of the member 23 is rounded and corresponds to the shape of the edge 13 of the member 13. The upper inner edge 23 of the member 23 overhangs the recess 21 in the carrier block 20.

Received within the recess 21 in the carrier member 20 is a movable block 24: which preferably has a central opening therein and which has a laterally extending flange portion 2 1i that is of substantially the same diameter as the inside diameter of the recess 21. This shoulder or ledge 24 is, free to move vertically with respect to the member 20, but itsdownward movement is limited by the shoulder 23 which overhangs a ledge 24?. Surrounding the reduced portion of the block 24 is a die block 25 corresponding generally to the die block 12 of the lower die. This die block 25 has an enlarged upper portion 25 which is of substantially the same diameter as the inside diameter of the outer ring 23, but the main portion of the block 25 is of less diameter than the inside diameter of the member 28 to provide an annular groove 26 of considerable depth between the members 23 and 25. This groove corresponds to the groove 16 of the lower die. There is an inwardly and upwardly inclined shoulder on the block 25 at 25*.

Passing through the rim portioni22 of the carrier block 20 and through the die block 23 are one or more, preferably two, ejector rods 27 corresponding to the ejector rods 17 of ti e lower die. These ejector rods are not different from those now generally provided on pressing devices of this general character.

In the manufacture of the couplings of the type referred to with the apparatus herein described, the bodies for the couplings are made by cutting standard pipe into suitable short lengths. A blank formed from a section of pipe is illustrated in Figure 1 of the drawings. This blank is set into the lower die when the two die members are spread apart. At this time the block 2 with its associated die block 25, is in its lowermost position, to which position it has been moved by gravity, and is retained against further downward movement by the co-operating shoulders 23 and 2 1. Although the lowermost ends of parts 24C and 25 clear the ends of the blank when the parts are spread to the greatest possible extent, the part 25 projects into the blank before the dies have moved to the position where they are closest together.

In like manner the block 7 with its associated die block 12 is urged upwardly by the spring 10 into the interior of the cylindrical blank. As the two die members are brought together, one of them, preferably the upper one, moving toward the other, the ends of the blank are subjected to pressure. That portion of the upper and lower dies which initially projects well into the blank serves to prevent the blank from bulging inwardly under the endwise pressure, so that, upon continued endwise pressure on the blank, the blank starts to bulge outwardly. As the pressure on the ends of the blank increases the member 7 with its cooperating parts is forced down againstthebottom plate 2, and the menu ber 24 with its cooperating parts is forced upwardly against the carrier block 20. Upon the continued pressing stroke, the central portion of the blank is bulged outwardly, the curved surfaces 13 and 23" serving to im part the proper curvature to the outwardly expanding metal of the blank. At the same time the ends of the blank are pressed against the inclined surfaces 12 and 25" to produce beveled ends on the blank.

When the two dies are in the position closest to each other, as shown in Figure 2, the blank has assumed the shape therein disclosed. The dies then move apart and the ejector rods 17 and 27 serve to force the cou pling out of the dies. When the coupling has been cleared of the dies, a new blank may be inserted and the operation repeated.

Upon completion of the pressing stroke the blank, if it is to be used for a welded pipe line, is finished and ready for use. If it is to be used as a threaded coupling, the opposite end portions thereof must be suitably threaded.

By forming the couplings from lengths of pipe which are of the same diameter as the pipe line in which the couplings are to be used, the couplings can be accurately made to the proper size. In the pressing of the blank to form the outward bulge, the metal flows outward naturally and without any such strain on the metal as would be likely to produce faults therein.

The apparatus is relatively simple and permits the couplings to be made on standard presses by the provision of suitable dies, such as those herein described. The blanks can be rapidly and cheaply manufactured with a substantial uniformity.

I claim: 7

1. Apparatus for the manufacture of expansion couplings including upperand lower die members, one of which is movable toward and away from the other, each of said die members having a relatively deep annular groove therein into which the end of a tubular blank can be inserted and by means of which the ends of the blank are. confined, the outer edge of the annular groove of each of the die members being outwardly rounded, said grooves having an inclined bottom therein for producing a taper on theopposite ends of the blank; I

2. Apparatus for the manufacture of expansion couplings including a pair of opposed die members, one of which is movable toward and away from the other, each of said die 7 members having an outer ring, and a cooperating circular block Within the ring of each die member concentric therewith and relatively movable with respect to'the ring members, a groove being formed between the outer ring members and the relatively movableinner members of the respective dies.

3. Apparatus for the manufacture of expansion pipe couplings including a pair of opposed die members, one of which is movable with respect to the other, each of said die members including a supporting plate, a ring shaped die member fixedly secured to the supporting plate of each member, a concentric block within the ring member of each die, said concentric block being slidably guided within the ring member whereby it has a relative movement with respect thereto, the inner portion of the inner-member being of substantially the same diameter as the inside of the ring member, the main portion of the inner member being of less diameter than the inside diameter of the ring member, whereby. a relatively deep groove is provided betwen the inner member and the ring member of each die, said groove being adapted to receive and confine the ends of a. tubular blank inserted between the dies.

l. Apparatus for the manufacture of expansion pipe couplings including a pair of opposed die members, one of which is movable with respect to the other, each of said die members including a supporting plate, a ring shaped die member fixedly secured to the supporting plate of each member, a concentric block within the ring member of each die, said concentric block being slidably guided within the ring member whereby it has a relative movement with respect thereto, the inner por ti on of the inner member being of substantially the same diameter as 'theinside of the ring member, the mainjportion of the concentric member beingof less diameter than the inside diameter of the ring member, whereby a relatively deep groove is provided betwen the inner member and the rlng member of each die,-

said groove being adapted to receive and confine the ends of a tubular blank inserted between the dies, said ring members having the inside outer edges thereof outwardly rounded.

5. Apparatus for the production of expansion couplings including a lower die member and an upper die member, said lower die member including a supporting plate having a contrally recessed portion, a forming ring carried on the supporting plate around the recessed portion thereof, a movable block having its inner end received within the recessed face of the supporting plate, said recessed block being vertically movable with respect to said plate, a springfor normally urging said block upwardly, said block having a die portion thereon which is of less diameter than the diameter of the ring portion and concentric therewith, an annular groove being provided between the ring member and the die portion of the block in which one end of a tubular blank can be received, said upper die member including a supporting plate having I a ring member thereon, a vertically movable block centrally disposed within the ring member and slidable with respect to the supporting plate, said block having its lower end portion of less diameter than the inside diameter of the ring whereby an annular groove is provided inside the ring of the upper die member in which the upper end of a tubular blank can be received and confined.

In testimony whereof I have hereunto set my hand.

PETER J. SHRUM. 

